Method of transmitting energy by electromagnetic waves.



R. A. FESSENDEN.

METHOD OF TRANSMITTING ENERGY BY ELECTROMAGNETIC WAT/ES.

' APPLICATION FILED MAY 12. 1906.

1,172,017. Patented Feb. 15,1916.

2 SHEETS-SHEET 1 11106721 3 I I I R. A. FESSENDEN. METHOD OF TRANSMITTING ENERGY BY ELECTROMAGNETIC WAVES.

' APPLICATION FILED MAY I2. 1906'. 1,172,017.

Patented Feb. 15, 1916.

2 SHEETS-SHEET 2;

UNITED STATES PATENT OFFICE. I

MESNE ASSIGNMENTS, TO SAMUEL M. KINTNER, OF PITTSBURGH, PENNSYLVANIA, AND HALSEY M. BARRETT, OF BLOOMFIELD, NEW JERSEY, RECEIVERS.

METHOD OF TRANSMITTING- ENERGY BY ELECTROMAGNETIC WAVES.

To all whom it may concern:

Be it known that I, REGINALD A. Freeman- DEN, citizen of the United States, and resident of Washington, District of Columbia, have invented certain new and useful Improvements in Methods of Transmitting Energy by Electromagnetic Waves, of which the following is a specification.

The invention herein described relates to the art of transmission of electrical energy, and more particularly to the transmission of energy byelectromagnetic waves, and

still more particularly to the transmission of telegraphic or telephonic signals.

My invention includes an improved method of signaling by commutating the source of energy, as hereinafter more fully described and claimed.

In the accompanying drawings forming a part of this specification, Figures 1, 2, 3 and 4 show forms of apparatus embodying my invention.

Heretofore in the practice of the art it has been customary to generate such high frequency oscillations as are used for generating electromagnetic waves by means of a spark gap, or a vacuum tube,,or a high frequency dynamo. It has been customary to produce an eifect at the receiving station by causing the electric oscillations to elfect an imperfect contact, or a perfect contact or to rectify the waves by means of a vacuum tube or to produce a direct dynamic action.

In the practice of my invention I employ a rapidly revolving commutating device, capable of transforming a continuous current into an alternating current, of high frequency, and also a receiving system capable of rectifying the same by transforming it into a continuous current. In Fig. 1 such a commutating device 'is shown.

The commutator is. preferably 'fixed andv has alternate segments 7, 7, 7 connected by wire 7, and intervening segments. 8, 8, 8 connected together by wire 8,.While intervening between the' segments, are insu-v lating segments 9, 9, 9. If the inside diameter of the commutator'be 8 inches and the commutator segments be of aninch-wide' Specification of Letters Patent.

Patented Feb. 15, 1916.

Application filed May 12, 1906. Serial No. 316,521.

ably flexible at the end and having an ad- ]ustable balance weight 6, and revolving at a speed of 500 revolutions per'second. l is an antenna, 3, l2 and 16 are condensers, preferably adjustable, 4, 10 and 11 are inductances or inductive resistances preferably adqustable, 13, 14 is a source of voltage and 2 1s a ground connection. On revolving the brush 5 the antenna 1 is put into contact alternately with one or the other set of commutator segments, and as the mid dle point 15 of the source of voltage is connected to ground, the aerial 1 is alternately charged above and below the potential of the earth at a frequency of 100,000 alternatlons per second. In this way electromagnetic waves are generated and can be usedtransmitting commutator, beats are pro-' duced of a lower or higher pitch in the telephone 20. Y 4

In Fig. 3 is shown a device used for wireless telephony; Here 1 is the antenna grounded at 2, 27 is a telephone transmitter, 22 22 is a transformer, 23 the commutating device, 24 and 25 a battery having its middle point 26 connectedto ground as shown.

In Fig. 4 is shown another form of wireless telephone where the antenna .1 is con-,

nected to the commutating device 28.. 32, 33 is the secondaryof an induction coil havingjts middle point 34 grounded at 2. 29

is the primary of an induction .coil, 30 .a

battery and 31 a telephone transmitter. In the operation of this latterdevice the transmitter 31- on being spoken into produces electric waves of corresponding intensity in the antenna -1, which being received at a receiving station reproduce the speech.

In the design of the commutating device here shown it is preferred that the brushes should revolve and the commutator be fixed. By this means all difliculties due to great loss of power from wind friction and friction of bearings and from difficulties in constructing a commutator to revolve at such high speeds without flying to pieces or becoming inoperative through unbalancing are overcome.

\Vhile only one brush and commutator is shown I do not limit myself to one brush or commutator as various arrangements may be used. Nor do I limit myself to the particular electrical arrangements shown as the invention herein described is widely appli cable and may be employed with any of the devices well known in the art.

It is to be noted that a commutator differs from a rectifier in that a commutator is capable of changing adirect current into an alternating current, as well as changing an alternating current into a direct current, Whereas a rectifier is only capable of rectifying an alternating current into a direct current. Moreover, a rectifier does not strictly change an alternating current into a direct current, but merely suppresses,onehalf of the alternating current. By the term commutating I will be understood to mean strictly the changing of one kind of current into the other continuously and Without loss of energy.

What I claim is: r

1. The method of transmitting energy by electro-magnetic waves by mechanically commutating the source of energy at the same frequency as the waves to be produced.

2. The method of transmitting energy by electro-magnetic waves by mechanically communicating a direct current into alternating current, and commutating the resulting alternating current into direct current at the receiving end.

3. In the art of transmittingenergy by high frequency electric oscillations, the method comprising producing high frequency currents by mechanically commutating the source, and commutating said currents as received to produce an indication without storing or losing the energy, substantially as described.

4. The method of signaling consisting in generating and receiving electro-magnetic waves by mechanically varying the potential to create oscillations in the sending con-.

ductor, and, commutating them in the receiving circuit.

5. The method of signaling consisting in mechanically generating oscillations by changing the potential of a sending conductor alternately above and below that of the ground connection at wave frequency,

and receiving said oscillations to produce signals by mechanically commutating them in a local circuit connected to a receiving antenna. I

6. The method of signaling by electromagnetic waves which comprises generation of oscillations by connnutating a source of direct current at a frequency corresponding to the waves it is desired to produce, receiving said waves on an absorbing antenna, connnutating the resulting alternating current therein into direct current and operating an indicator thereby, substantially as described.

7. The method of generating and receiving electro-magnetic waves by mechanically commutating the current at the frequency of the waves.

8. The method of transmitting energy which comprises generatinghigh frequency oscillations by mechanically commutating a source of' current at the frequencyof' the waves it is desired to produce, and receiving said waves by commutating and thereby transforming them into direct current at the receiving station.

9. The method of signaling by electromagnetic waves which comprises mechanically coimnutating a source of current to produce the oscillations, and mechanically commutating the resulting alternating current at the receiving station to transform the same and effect a receiving instrument.

10. The method of producing high frequency oscillations by mechanically connecting a radiating circuit alternately with points of different potential in a circuit containing a current source, such commutation being at the frequency of the waves, desired to be produced.

11. The method of signaling by electromagnetic waves which comprises the transforming of direct current into high frequency alternating current by a mechanical commutator at the sending end and transforming the alternating current into direct current by a similar mechanical commutator of approximately the same frequency at the recelving end.

12. In wireless telegraphy, the method of generating current for radiating Hertzian oscillations, which comprises charging the radiatingdevice from a continuous source at separated intervals svnchronous with the time period of the oscillations, substantially as described.

13. In wireless telegraphy, the method of generating oscillations by alternately connecting and disconnecting a radiator with a source of-potential at a frequency the same as the time period of the oscillations to be generated, substantially as described.

14. Apparatus for transmitting energy by electro-magnetie waves, comprising a mechanical commutator operating to commutate the currents at the same frequency as r the waves used in the transmission, substantially as described. e

15. Apparatus for transmittingenergy by no I electro-magnetic waves, comprising a mechanical commutator at each of two statlons one operating to commutate'the source of current into high frequency oscillations, and

the other operating to commutate the resulting alternating current into direct current.

16. A tuned circuit connected with a voltage source, a connection from a point of intermediate voltage in said source to the ground, combined with an antenna and ain the source havlng difi'erent potentials with frequency high enough to produce electromagnetic waves, and a telephone transmitter in the antenna circuit adapted to modify said stream of waves in accordance with speech. v

18. In wireless signaling apparatus, a circuit comprising an inductance and a capacity and having a natural period of osclllation and being adapted to cause radiation of energy at a high oscillation frequency, a source of voltage, and a rotating device connected to alternatelycharge the capacity in different directions at a rate dependent upon the speed of rotation, substantially as described.

19. Apparatus for t'ra nsmitting electrical energy comprisinga current source and a commutator operating to continuously pro:

duce high frequency oscillations therefrom, a receiving circuit including a receiver operable by continuous current and a commutator operating to change the received currents into direct currents, to produce an effect on the receiver, substantially as described.

20. In wireless signaling apparatus, the combination with a current source and an antenna, of a commutator alternately connecting the antenna with points of diflerent voltage on the source at wave frequency.

21. In transmitters for wireless telegraphy, the combination with a sending cir cuit, of mechanically operated means for positively completing and interrupting saidcircuit synchronously with the time period of Hertzian oscillations of definite fre quency.

22. In transmitters for wireless telegraphy, thecombination with a sending circuit, of mechanically operated means for positively reversing the current in said circuit synchronously with the time period of Hertzian oscillations of definite frequency.

23. In a transmitter for wireless telegraphy, the combination with an oscillatory circuit, of mechanically operated means for positively completing and interrupting said circuit synchronously with its time period of each oscillation.

24. In transmitters for wireless telegraphy, the combination of an oscillatory circuit, a condenser therein, means for supplying current for charging the condenser, and mechanically operated means for positively discharging said condenser synchronously with the time period of each osclllation. a 25. In transmitters for wireless telegraphy, the combination with an oscillatory circuit, of a sectional generator wheel means cooperating with the sections of said wheel to produce oscillations 1n said oscillatory circuit, and means for rotating said means at a definite speed to complete and interrupt said circuit synchronously with the time period of each OSClllatlOD. V

Signed at Brant Rock, in the county of Plymouth and State of Massachusetts this tenth day of May A. D. 1906.

REGINALD A. FESSENDEN. Witnesses: Jsssm E. BENT, PHILIP T. Pos'r. 

